Batman Begins has made its debut at number one at the North American box office, taking $49.9m (£25.7m).

But the film's performance failed to halt a long-term decline in box office takings in the US and Canada, which marks the worst slump for 20 years.

The top 12 films registered a 1.6% downturn on the same weekend in 2004.

Hilary Duff's new film The Perfect Man was the other major new release at seven, making less than half of her 2004 film A Cinderella Story.

Box office analysts are considering whether a growing preference for watching films at home is eroding cinema performance.

TOP FIVE US FILMS

1 Batman Begins

2 Mr And Mrs Smith

3 Madagascar

4 Star Wars Episode III - Revenge Of The Sith

5 The Longest Yard

Source: Exhibitor Relations

But Dan Fellman, head of distribution for Warner Brothers, says this is a trend which will require further observation.

"We need to look at that, but I believe you can't do it by looking at six months. I think you have to take a couple of years to look at it," he said.

Mr Fellman added that he did not believe there has been a strong enough roster of films in recent months.

Sequel

"Even though there were and will continue to be strong movies in the summer, I don't think there have been enough of them," he said.

Batman Begins, which stars Welsh actor Christian Bale in the lead role, is forecast to end its first week on $85 million, compared to a range of $59 million to $77 million for the previous outings in their initial period of release.

Dan Fellman, responsible for the distribution of Batman Begins, said the studio was likely to produce a sequel on the strength of this film's performance.